Back-Side Interface for Hand-Held Devices

ABSTRACT

An electronic device uses separate surfaces for input and output. One of the surfaces (e.g., the bottom) includes a force-sensitive touch-surface through which a user provides input (e.g., cursor manipulation and control element selection). On a second surface (e.g., the top), a display element is used to present information appropriate to the device&#39;s function (e.g., video information), one or more control elements and a cursor. The cursor is controlled through manipulation of the back-side touch-surface. The cursor identifies where on the back-side touch-surface the user&#39;s finger has made contact. When the cursor is positioned over the desired control element, the user selects or activates the function associated with the control element by applying pressure to the force-sensitive touch-surface with their finger. Accordingly, the electronic device may be operated with a single hand, wherein cursor movement and control element selection may be accomplished without lifting one&#39;s finger.

This application claims priority to U.S. patent application Ser. No.11/115,539 entitled “Hand Held Electronic Device with Multiple TouchSensing Devices” by Duncan Robert Kerr, Steve Hotelling and Brian Huppi(filed 26 Apr. 2005). The subject matter claimed herein is also relatedto subject matter described in U.S. patent application Ser. No.11/278,080 entitled “Force Imaging Input Device and System” by SteveHotelling and Brian Huppi (filed 30 Mar. 2006), Ser. No. 11/382,402entitled “Force and Location Sensitive Display” by Steve Hotelling(filed 9 May 2006) and 10/840,862 entitled “Multipoint Touchscreen” bySteve Hotelling and Brian Huppi (filed 6 May 2004) and, all of which arehereby incorporated by reference.

BACKGROUND

The invention relates generally to user input for computer systems andmore particularly to a touch and force-sensitive back-side interface forhand-held electronic devices (e.g., hand-held electronic and computerplatforms).

An increasingly popular form of electronic device is the hand-heldmulti-media device. Illustrative devices of this type include palm orhand-held personal computers, tablet computer systems, mobiletelephones, personal digital assistants, portable video players andportable audio players. One specific example of such a device is thevideo iPod® from Apple Computer. (IPOD is a registered trademark ofApple Computer, Inc.) In this class of device the display screen,typically a liquid crystal display (“LCD”), is often to small to makeeffective use of finger based touch input. Although a touch-screeninterface could be embedded in or overlaid on the display, the use ofeven a single finger for input may occlude a significant portion of thedisplay or cover more than a single operational control element. Whilethis problem could be mitigated by limiting the touch area to a portionof the display screen (e.g., the display edges where horizontal orvertical motion could emulate slider controls), a single finger couldstill cover a substantial amount of the useful display area. Inaddition, display smudging is a problem as with all finger sensitivetouch-screen interfaces. While stylus based touch-screens may be used topartially reduce the occluding problem and eliminate smudging, theysuffer a large disadvantage compared to finger based touch-screensystems in that they require the storage and removal of a stylus. Inaddition, for small hand-held devices a stylus input requires the use oftwo hands: one to hold the device and one to hold and manipulate thestylus.

SUMMARY

In one embodiment the invention provides a method to operate anelectronic device. The method includes displaying first informationappropriate to the device's function on a display element on a topsurface of the electronic device (e.g., video, graphic or textualinformation), displaying one or more control elements and a cursor onthe display element (e.g., numeric or alphanumeric keys, buttons,sliders and control wheels), adjusting the cursor's displayed positionin response to an object contacting a force-sensitive touch-surface onthe device's bottom surface, and activating or executing a functionassociated with one of the control elements when the cursor ispositioned “over” the control element and a force is applied to theforce-sensitive touch-surface at a position corresponding to the cursor.In a preferred embodiment, the control elements are displayedtransparently so that the first information is not totally occluded bythe display of the control elements. A program implementing the methodmay be stored in any media that is readable and executable by a computerprocessor.

In another embodiment, the invention provides an electronic device thatmay be operated in accordance with the described method. Illustrativeelectronic devices of the type described and taught herein include, butare not limited to, hand-held computer systems, tablet computer systems,personal digital assistants, portable video playback system, portableaudio playback systems and mobile telephones.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a prior art hand-held multi-mediadevice.

FIG. 2 shows, in cross-section, a hand-held multi-media device inaccordance with one embodiment of the invention.

FIGS. 3A and 3B show one embodiment of a multi-media hand-held device inaccordance with the invention.

FIG. 4 shows another embodiment of a multi-media hand-held device inaccordance with the invention wherein alpha-numeric input controlelements are provided.

FIG. 5 shows yet another embodiment of a multi-media hand-held device inaccordance with the invention wherein alpha-only input control elementsare provided.

FIG. 6 shows, in block diagram format, an electronic device inaccordance with one embodiment of the invention.

DETAILED DESCRIPTION

The following description is presented to enable any person skilled inthe art to make and use the invention as claimed and is provided in thecontext of the particular examples discussed below, variations of whichwill be readily apparent to those skilled in the art. Accordingly, theclaims appended hereto are not intended to be limited by the disclosedembodiments, but are to be accorded their widest scope consistent withthe principles and features disclosed herein.

Small multi-media hand-held devices such as mobile telephones and videoplayback units typically divide their front surface into an outputregion (through which video or graphic information is presented) and aninput region (comprising one or more control elements through which auser operates the device). An illustrative prior art device that is laidout in this manner is the iPod® from Apple Computer, Inc. As shown inFIG. 1, the output region of iPod® 100 comprises LCD 105 and the inputregion comprises a single multi-function control element—spin orclick-wheel 110.

In contrast, a multi-media device in accordance with the invention usesseparate device surfaces for input and output. More specifically, aforce-sensitive touch-surface is provided on a first or back-sidesurface of the device through which a user provides input (e.g., cursormanipulation and control element selection/activation). On a second orfront-side surface, a display element is used to present one or morecontrol elements and a cursor that is controlled through manipulation ofthe back-side touch-surface. When the device is activated or placed intoan operational state where it is appropriate, control elements (e.g.,soft keys and menus) are displayed on the display element. The soft keysmay be opaque or transparent (so as not to occlude prior displayedinformation such as a video presentation, a picture, a graphic ortextual information). The displayed cursor identifies where on theback-side touch-surface the user has their finger. When the cursor ispositioned over the desired control element/soft key (i.e., spatiallyoverlapping on the display element), the user selects or activates thecontrol element by applying pressure to the force-sensitivetouch-surface with their finger. Accordingly, the invention provides ameans to operate a hand-held electronic device with one hand, whereincursor movement and control element selection/activation may beaccomplished without lifting one's finger.

Referring to FIG. 2, a cross-sectional view of multi-media hand-helddevice 200 in accordance with one embodiment of the invention includesdevice housing 205, top surface 210 having display element 215 andbottom surface 220 having force-sensitive touch-surface 225. As usedherein, a force-sensitive touch-surface is a surface that is adapted tosimultaneously detect where one or more objects touch it (e.g., fingers)and the force those objects apply to the surface. Illustrativeembodiments of force-sensitive capacitance-based touch-surfaces aredescribed in the documents identified in paragraph [0001] above.Illustrative display elements include LCD panels.

Referring to FIG. 3A, hand-held multi-media device 300 in accordancewith one embodiment of the invention incorporates the functionality ofclick-wheel 305 on the device's force-sensitive touch-surface 225 (onbottom surface 220). Click-wheel 305 may be represented on touch-surface225 by, for example, an etched or raised outline. Referring to FIG. 3B,when the user activates click-wheel 305, navigation menu 310 andclick-wheel 315 are shown. Also displayed is cursor 320 which shows theposition of the user's finger against the back-side touch-surfacerelative to click-wheel 315. In the illustrated embodiment, navigationmenu 310 and click-wheel 315 are rendered transparently (denoted bydashed lines in FIG. 3B) so that the user may continue to view whateverinformation was being displayed at the time they activated the back-sidecontrol. Once the user manipulates cursor 320 by sliding their fingeracross force-sensitive touch-surface 225 to the desired position (e.g.,the “pause” control element position on click-wheel 315), all the userneed do is apply pressure with that finger to the force-sensitivetouch-surface to activate the desired action. Thus, a user may move thedisplayed cursor and make a selection (aka a “mouse-click”) withoutlifting their finger from surface 225. In this manner multi-media device300 may be controlled by the user with a single hand.

In another embodiment, a multi-media hand-held device such as device 300may provide more than a single control element. In embodiments of thistype, each control element (e.g., button, key, slider or click-wheel)may have an etched counterpart on back-side touch-surface 225, with eachbeing displayed as desired (one at a time depending upon where theuser's finger is detected, or all at once). In yet another embodiment,control element outlines are not etched or otherwise denoted onback-side touch-surface 225.

While the interface of FIGS. 3A and 3B may be effective for selectingitems from a list, it is not as convenient for alphanumeric input.Accordingly, in another embodiment of the invention one or more controlelements may be displayed when the device's back-side force-sensitivetouch-surface is activated (see discussion below). Referring to FIG. 4,in one embodiment suitable for a device that incorporates mobiletelephone capability, device 400 displays numeric soft keys 405 ondisplay screen 215 situated on front surface 210. The user may select oractivate one or more of the displayed buttons by moving their finger(s)across back-side force-sensitive touch-surface 225 so as to positioncursor 410 above (i.e., spatially coincident with) the desired button.Selection may be made by applying pressure to the back side of thedevice as discussed above. For the user's convenience, previouslyselected numbers 415 may be displayed.

Referring to FIG. 5, in yet another embodiment in accordance with theinvention, device 500 displays alpha soft keys 505 on display element215 on front surface 210. By selecting various keys 505, the user mayenter character strings (e.g., string 510). As before, the userpositions cursor 515 through movement of their fingers across thedevice's back-side force-sensitive touch-surface; button selection ismade through the application of pressure to the back-side touch-surface.As shown, device 500 displays alpha buttons 505 transparently so thatthe user may continue to view information that may be displayed“beneath” them. Of course, buttons 505 may be opaque.

In still another embodiment, a multi-media hand-held device having aback-side force-sensitive touch-surface may utilize two or more of theinterfaces described above. For example, in a first mode (e.g., a musicplayback mode), the click-wheel interface described above with respectto FIGS. 3A and 3B could be employed (with or without backside surfaceetching). In another mode (e.g., a telephone mode), the interfacedescribed above with respect to FIG. 4 could be implemented. In stillanother mode (e.g., text input, electronic mail or instant messagingmodes) the alpha interface described in connection with FIG. 5 may beused. Other interfaces will be apparent to one of ordinary skill in theart having the benefit of this disclosure.

In some embodiments, the display of control elements and/or a menu maybe triggered by a specific user action. For example, by the user holdingtheir finger on back-side touch-surface 225 within the region defined byan etched control element (e.g., click-wheel 305) for a specified periodof time (e.g., one second). Another user action to trigger activation ofa mode-appropriate user interface would be to simply hold one or morefingers against the back-side force-sensitive touch-surface for aspecified period of time and with at least a minimum specified force(e.g., a “light” grip or poke).

Alternatively, a change in device 200's operational state may cause thesame result. For instance, appropriate control element or menu may bedisplayed when device 200 transitions from a first state to a secondstate. Illustrative operational states include, but are not limitedto—on, off, locked, phone mode, video play mode, audio play mode,calendar mode, email mode, address book mode and image capture mode.Thus, a single user action may have cause different control elements tobe displayed (or no control elements at all), depending on the device'scurrent operational state.

Referring to FIG. 6, an illustrative implementation of hand-heldmulti-media device 200 includes force-sensitive touch-surface controller600, processor 605, memory 610 and display element controller 615.Controller 600 provides the necessary drive and sensing circuitry toobtain location and force information from force-sensitive touch-surface225. In a typical implementation, touch-surface 225 is comprised of anumber of sensing elements arranged in two-dimensional array. Eachsensing element (aka “pixel”) generates an output signal indicative ofthe electric field disturbance (for capacitance sensors), force (forpressure sensors) or optical coupling (for optical sensors) at thesensor element. The ensemble of pixel values at a given time representsa “proximity image.” Touch-surface controller 600 provides this data toprocessor 605 or to memory 610. Processor 605, in turn, processes theproximity image information to correlate the user's finger movementacross touch-surface 225 with the displayed information. Memory 610 mayinclude one or more of the following types of storage media: magneticdisks; optical media; and semiconductor memory devices such as staticand dynamic random access memory (RAM), Electrically ProgrammableRead-Only Memory (“EPROM”), Electrically Erasable Programmable Read-OnlyMemory (“EEPROM”), Programmable Gate Arrays and flash devices. Displaycontroller 615 is responsible for producing the display element signalsnecessary to actually display information.

Various changes in the materials, components, circuit elementstechniques described herein are possible without departing from thescope of the following claims. For instance, illustrative multi-mediahand-held device 300 has been described as including an etched controlelement on its back-side touch-surface. This is not necessary. Further,multimedia devices in accordance with the invention may include physicalbuttons/switches in addition to a force-sensitive touch-surface (e.g.,power, mute and reset buttons). In addition, processor 605 may be asingle computer processor, a special purpose processor (e.g., a digitalsignal processor or “DSP”), a plurality of processors coupled by acommunications link or a custom designed state machine. Custom designedstate machines may be embodied in a hardware device such as anintegrated circuit including, but not limited to, application specificintegrated circuits (“ASICs”) or field programmable gate array(“FPGAs”). Processor 605 may also execute program instructions stored inmemory 610 to perform the acts described herein.

1. A method for operating a hand-held electronic device, comprising:displaying first information on a display element on a first surface ofa hand-held electronic device; displaying control elements and a cursoron the display element when the electronic device is in a specifiedstate; adjusting a display position of the cursor in response to acontact on a force-sensitive touch-surface on a second surface of theelectronic device, the second surface being a different surface than thefirst surface; and activating a function associated with a firstdisplayed control element when the cursor is positioned coincident withthe first displayed control element and an activation force is appliedto the force-sensitive touch-surface at a position corresponding to thecursor.
 2. The method of claim 1, wherein the act of displaying controlelements comprises displaying one or more control elements selected fromthe list consisting of a button, a slider, a spin-wheel, a numeric inputkey, an alpha input key and an alpha-numeric input key.
 3. The method ofclaim 1, wherein the act of displaying control elements comprisesdisplaying translucent control elements.
 4. The method of claim 3,wherein the act of displaying translucent control elements is performedso that the first information remains at least partially visible throughthe control elements.
 5. The method of claim 1, wherein the act ofdisplaying control elements comprises displaying opaque controlelements.
 6. The method of claim 1, wherein the act of displayingcontrol elements further comprises displaying one or more menu items,wherein the one or more menu items identify at least one operation. 7.The method of claim 1, wherein the act of displaying a cursor comprisesdisplaying a translucent cursor.
 8. The method of claim 1, wherein theact of activating is performed continuously with the act of adjusting sothat the contact does not leave the surface of the force-sensitivetouch-surface.
 9. The method of claim 1, wherein the specified state isassociated with an operational mode of the hand-held electronic device.10. The method of claim 9, wherein the operational mode comprises atelephone mode.
 11. The method of claim 9, wherein the operational modecomprises a alpha-numeric data entry mode.
 12. The method of claim 9,wherein the operational mode comprises a character-based input mode. 13.The method of claim 1, wherein the act of adjusting comprises trackingthe contact as it moves about the force-sensitive touch-surface.
 14. Themethod of claim 1, wherein the hand-held electronic device comprises amobile telephone.
 15. The method of claim 1, wherein the hand-heldelectronic device comprises a hand-held computer system.
 16. The methodof claim 1, wherein the hand-held electronic device comprises a personaldigital assistant.
 17. The method of claim 1, wherein the hand-heldelectronic device comprises a video display unit.
 18. The method ofclaim 1, wherein the hand-held electronic device comprises a digitalmusic device.
 19. A program storage device, readable by a processor,comprising instructions stored thereon for causing the programmablecontrol device to perform the method in accordance with claim
 1. 20. Ahand-held electronic device, comprising: a first surface having adisplay element coupled thereto; a second surface having a touch-surfacecoupled thereto, the second surface not coplanar with the first surface,the touch-surface adapted to detect a location on the touch-surfacecontacted by an object and an activation force applied to thetouch-surface by the object; and control means for— displaying on thedisplay element first information, control elements, and markrepresenting the contact's location on the touch-surface, determiningwhen the mark is spatially coincident with one of the control elements,determining the activation force is greater than a specified threshold,and activating a function associated with the one control element. 21.The hand-held electronic device of claim 20, wherein the devicecomprises a mobile telephone.
 22. The hand-held electronic device ofclaim 20, wherein the device comprises a video playback device.
 23. Thehand-held electronic device of claim 20, wherein the device comprises anaudio playback device.
 24. The hand-held electronic device of claim 20,wherein the device comprises a personal digital assistant.
 25. Thehand-held electronic device of claim 20, wherein the first informationcomprises one or more of the following types of information: video,graphic and textual.
 26. The hand-held electronic device of claim 25,wherein the first information is displayed opaque.
 27. The hand-heldelectronic device of claim 20, wherein the control elements comprise oneor more of a button, a numeric key, an alpha key, a slider, aclick-wheel and a menu.
 28. The hand-held electronic device of claim 20,wherein one or more of the control elements are transparent.
 29. Thehand-held electronic device of claim 20, further comprising one or morephysical buttons coupled to a surface of the device.
 30. The hand-heldelectronic device of claim 29, wherein one of the one or more physicalbuttons comprises a power button adapted to turn-off the displayelement.
 31. The hand-held electronic device of claim 20, wherein themeans for displaying is activated after a contact to the second surfacehas been made and held substantially in one place for a specified periodof time.
 32. The hand-held electronic device of claim 20, furthercomprising at least one etched button on the second surface, the atleast one etched button corresponding to a displayed control element.